Electric motor and electric pump

Abstract

An electric pump has a pump body, a pump magnet received in the pump body, an impeller received in the pump body and fixed to the pump magnet, and a disc type electric motor. The electric motor includes a stator, disc type coils fixed to a surface of the stator, a rotor rotatably positioned above the coils, and a circuit board electrically connected to the coils. The rotor has a rotor magnet positioned beneath the pump body and magnetically coupled to the pump magnet. When the coils are energized, an axial magnetic field is generated to drive the rotor and, through the magnetic coupling between the rotor magnet and the pump magnet, rotate the impeller.

1 . An electric pump, comprising:
 a pump body;   a pump magnet rotatably disposed in the pump body;   an impeller disposed in the pump body and fixed to the pump magnet; and   a disc type electric motor positioned beneath the pump body for rotating the magnet and the impeller, the disc type electric motor comprising a stator and a rotor, the stator comprising:   a stator core,   a number of disc type coils fixed to a surface of the stator core, and   a circuit board positioned on an end of the stator and electrically connected to the disc type coils,   the rotor comprising a rotor magnet positioned between the disc type coils and the pump body, the magnet being positioned confronting the pump magnet to produce a magnetic coupling between the rotor magnet and the pump magnet,   wherein when electrical power is applied to the circuit board, the disc type coils generate an axial magnetic field to drive the rotor, thereby rotating the pump magnet and the impeller.   
     
     
         2 . The electric pump of  claim 1 , further comprising a plurality of fasteners securing the disc type electric motor to the pump body. 
     
     
         3 . The electric pump of  claim 2 , wherein spaced tabs extend radially from the stator, each tab has a through hole, the fasteners engage the through holes to secure the disc type electric motor to the pump body. 
     
     
         4 . The electric pump of  claim 1 , further comprising an iron sheet fixed to the pump magnet, providing a flux return path. 
     
     
         5 . A disc type electric motor, having a stator and a rotor, the stator comprising:
 a stator core;   a number of disc type coils fixed to a surface of the stator core;   a circuit board positioned on an end of the stator core and electrically connected to the disc type coils,   the rotor rotatably positioned above the disc type coils and comprising a rotor magnet; and   wherein when the circuit board is energized, the disc type coils generate an axial magnetic field to rotate the rotor.   
     
     
         6 . The motor of  claim 5 , wherein the stator has a plurality of grooves and through holes through which ends of windings of the disc type coils pass. 
     
     
         7 . The motor of  claim 5 , wherein the stator core has a plurality of first through holes arranged in the circumferential direction, through which the windings of the disc type coils pass to reach a lower surface of the stator core. 
     
     
         8 . The motor of  claim 5 , further comprising a plurality of bobbins, a plurality of positioning members, and a plurality of second through holes formed in the stator core and arranged in the circumferential direction, wherein the disc type coils are wound around the bobbins, each bobbin defines a third through hole, and each positioning member extends through a respective third through hole and a respective second through hole to secure a respective bobbin to the stator core. 
     
     
         9 . The motor of  claim 5 , wherein the rotor magnet is annular with a plurality of grooves formed in a radially inner surface and spaced in the circumferential direction, a solid glue is applied to the grooves to secure the rotor magnet to a shaft of the rotor. 
     
     
         10 . The motor of  claim 5 , wherein the disc type electric motor further comprises a solid glue layer, the solid glue layer is applied on an lower surface of the stator core and covers exposed parts of the windings of the coils. 
     
     
         11 . An electric pump, comprising:
 a pump body;   a pump magnet received in the pump body;   an impeller received in the pump body and fixed to the pump magnet;   a disc type electric motor for rotating the pump magnet and the impeller; and   an iron sheet fixed between the pump magnet and the impeller.   
     
     
         12 . The pump of  claim 11 , wherein the disc type electric motor has a stator and a rotor, the stator comprising:
 a stator core;   a number of disc type coils fixed to a surface of the stator core;   a circuit board positioned on an end of the stator core and electrically connected to the disc type coils,   the rotor comprising a rotor magnet rotatably positioned above the disc type coils; and   wherein when the circuit board is energized, the disc type coils generate an axial magnetic field to rotate the rotor.